Question: What is your favourite bacteria?

Karen Adler answered on 19 Sep 2025:

My favourite bacteria is Pseudomonas aeruginosa! Most bacteria (with a few exceptions) grow as white or cream coloured colonies on a petri dishg, but P. aeruginosa is usually a lovely light green as a result of it making less-than-lovely toxins that are blue and yellow. However, some strains can be neon highlighter yellow, deep turquoise, dark grey, even dark red! https://pbs.twimg.com/media/F5k4OFDaYAAuBBa?format=jpg or https://pbs.twimg.com/media/GOlCoifbwAA8IGe?format=jpg
They make a chemical that smells a bit like grape candy too, it is very strange! They have several tails (called flagella) all coming out together like a ponytail, so they are very good swimmers! Here is a video I recorded through the eyepiece of a microscope with my phone, you can see their shadows swimming around (not sped up) https://drive.google.com/file/d/1BnUyRwAfi4BmMUFxgWa1Pu2kosM9rSHU/view?usp=sharing

However, they are quite nasty… they can cause really terrible infections, especially in patients with burns or people who have cystic fibrosis. They are also very often resistant to multiple types of antibiotics – so my research involves trying to kill them!